Abscess of the mitral-aortic confluence and perforation of the mitral valve in a patient with Brucella endocarditis]

We report a case of Brucella aortic valve endocarditis in a 36 year-old patient with no underlying heart disease who required urgent surgery. In the postoperative follow-up, he suffered from congestive heart failure due to an anterior mitral valve rupture. In the echocardiogram, a periprosthetic abscess was seen and a second intervention was necessary. This report suggests that treating Brucella endocarditis requires a combined medical and surgical approach.     

Plant health clinics in Bolivia 2000—2009: operations and preliminary results

Smallholder farmers need information on plant diseases. Ten plant health clinics (Postas para Plantas) evolved in Bolivia after 2000 and are still operating due to the efforts of three local institutions. The plant clinics receive any problem, on any crop, and give written and verbal recommendations, immediately if possible. Many clinics are held at weekly farm fairs, where villagers from many surrounding communities can seek help. The clinic staff write fact sheets for farmers on common problems. From 2000 to early 2009 the clinics received more than 9000 queries on over 100 crops with potato comprising two thirds of the queries, followed by peach, tomato and broad bean. Potato tuber moth and potato weevil were by far the most dominant plant health problems in the high Andes, but not in lowland areas. The diversity of crops and problems are a big challenge to the clinic staff. With basic training and practical experience they learn to diagnose most problems. However, they need access to expert support to solve some of the more difficult problems and improve the quality of advice. Preliminary results show cases of poverty alleviation, reduction in pesticide abuse, increased harvests and other benefits. The plant health clinics in Bolivia enabled extension and research to reach more farmers with a timely low-cost service.     

Realization and dissemination of units in a revised SI

The General Conference of Weight and Measures (CGPM) with its Resolution 12 has officially prospected the adoption, possibly at the next General Conference of 2011, of new definitions for kilogram, ampere, kelvin and mole using fundamental constants as reference quantities. Thus, the outlines and features of the SI after that date are worthy to be considered and a general afterthought of the metrological activity in the new situation to be attempted.The future realisations of units will greatly benefit from the accelerated endeavour to determine the relevant fundamental constants with the minimum possible uncertainty before their values are fixed by definition. In fact, many of those experiments will become realisations of units when the new definitions are adopted.To define the units by reference to fundamental constants implies to abandon the identification of the unit with its primary standard, as in the old metrological tradition. To realise a unit will definitely consist in assigning a value to a primary standard, consistent with the fixed values of the reference constants, by means of an experimental procedure, independent of a specific definition, which could even not exist. The primary standard should be suitable to dissemination by direct comparison, thus essentially stable and accessible with the highest precision, while the role of the realisation experiment would be mainly related to indirect measurements, typical of scientific activity, which involves the coherence of the unit system. The two distinct roles, of unit realisation and primary standard, correspond to different uncertainty components, of which only one is implied in dissemination activity, just aiming at compatibility of measurements of a specific quantity. Each of the two uncertainty components has a different evolution from the time of the unit redefinition.These last considerations could validly contribute in critical issues, such as deciding whether the time for a unit redefinition has come or it should be preferable to wait for new and better experiments before fixing the value of a constant. This could be the case for the kilogram redefinition.     

Assignment of FIR Laser Lines of Hydrazine

With 228 known FIR laser emissions, hydrazine is the most prolific laser active molecules after methanol. But, due to the complexity of its rovibrational spectrum, only a few assignments of hydrizine FIR laser transitions are found in literature. Here we analyze 44 FIR laser lines of hydrazine excited by 20 different CO₂ pumps. The pump transitions are compared to available assignments of IR amino-wagging transitions. We propose values for the J and K quantum numbers involved in 41 FIR laser transitions, for 22 of them we give also the symmetry species.     

Successful Long-Term Central Venous Access

Daily home hemodialysis (DHHD) requires simple, vascular access to minimize patients' discomfort but also to guarantee tolerance and long-term efficiency. The arteriovenous fistula is not ideal for DHHD because of the double puncture required every day; in addition, the rate of dysfunction is probably greater because of the more frequent use. Central venous catheters may be a good alternative to the arteriovenous fistula as long-term vascular access for DHHD. In this study we report our experience with the internal jugular vein two-catheter access for long-term dialysis and evaluate its possible use for DHHD. Since 1988, Tesio's twin catheters have been positioned in 908 patients with exhausted peripheral vascular bed. In all patients hemodialysis could be performed a few minutes after the surgical procedure. The survival rate of catheters, in a selected group of 46 patients, at 1, 2, and 5 years was, respectively, 92%, 87%, and 82%. The mean blood flow was 282±29 mL/min at 1 month, 286±36 mL/min at 1 year, and 274±37 mL/min at 5 years. Venous pressure in the inlet side was 102±31 mm Hg at 1 month, 126±36 mm Hg at 1 year, and 132±58 mm Hg at 5 years. Catheter clotting was treated either with thrombolytic agents or with catheter (one or both) replacement. Sepsis was treated with systemic antibiotic therapy or catheter removal. Data support the potential role of the internal jugular vein two-catheter system for DHHD.     

Differences in sleep variables, blood adenosine, and body temperature between hypothyroid and euthyroid rats before and after REM sleep deprivation

Sleep deprivation causes an increase in energy expenditure in animals. Thyroid gland function has been related to metabolic function, and this may be compromised in sleep manipulations. The objectives of the present study were the following: 1) to develop a model of hypothyroid rats by surgical removal of thyroid glands without extirpation of the parathyroid; 2) to observe the sleep architecture in euthyroid (Etx) and hypothyroid (Htx) rats, both before and after rapid eye movement (REM) sleep deprivation (96 hours); 3) to challenge both groups (i.e. Etx and Htx) with REM sleep deprivation (96 hours) and then evaluate the effects on temperature; and 4) to measure the levels of adenosine and thyroid hormones in blood. One-month-old Wistar male rats (weight 90-100 g) were studied. The thyroid gland was removed, and the parathyroid glands were reimplanted within the neck muscle (Htx) under halothane anesthesia. A sham-operated group was also included (Etx). Four months later, the animals were studied according to the following protocols. Protocol 1: Animals of both groups (i.e. Etx and Htx) were implanted for sleep recordings. After a baseline polysomnography, these animals were REM sleep deprived by the platform method (96 hours). Protocol 2. An intraperitoneal temperature transducer was placed into animals of both groups under deep halothane anesthesia. They were studied at baseline, during 96 hours of REM sleep deprivation, and on the rebound period. Protocol 3: Plasma thyroid hormones [T3, T4, and thyroid-stimulating hormone (TSH)] and plasma adenosine were determined in both groups. Results of protocol 1 indicated that the main difference observed in Htx rats during the baseline sleep was an increase in delta sleep (slow-wave sleep 2) and a reduction in waking time compared with Etx animals. REM sleep rebound after 96 hours of REM sleep deprivation was similar in both groups. In protocol 2, the main finding was that Htx animals had reduced body temperature. A significant difference in body temperature between Etx and Htx animals was found mainly during lights-on period. REM sleep deprivation in the Etx group produced an increase in body temperature. Htx animals showed the opposite effect, with a reduction in body temperature during and after REM sleep deprivation. In protocol 3, the main findings were that Htx animals exhibited a significant reduction in blood thyroid hormones (T3, T4), and that they also had high levels of plasma adenosine. REM sleep deprivation produces changes in temperature regulation. The increase in body temperature during REM sleep deprivation may require thyroid integrity. Absence of the thyroid gland does not seem to influence REM sleep recovery after its deprivation. The high plasma adenosine levels found in the Htx group may explain the increase in delta sleep in this group.